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Number of Case Properties: The more properties a case has, the larger its size.
Data Types (e.g., text, integers, dates, multimedia): For example, text fields typically consume more space than integer fields.
Case History: CommCare tracks changes to case properties over time. A detailed case history with many updates can increase the overall size of the case.
Case Relationships: Parent-child relationships add metadata to the case, contributing to its size.
Multimedia Attachments: If a case includes multimedia files (e.g., images, audio recordings), these files significantly increase the size of the case.
Form Submissions: The number and complexity of form submissions linked to a case also affect its size. Each form submission can update case properties and add to the case history.
App Complexity: CommCare allows for incredibly complex apps–employing multiple data types, advanced functions, repeat groups, lookup tables, and more. This can result in redundancies, complex hierarchies, and an increase in the number of data fields that need to be stored.
Case sharing: This will not add to the Case Size, but may require more frequent syncing in order to maintain up-to-date information.
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Again, there is no definitive answer, due to the question types that are available (e.g. Lookup Tables, Multimedia Capture) as well as the complexity of calculations that you can have on your forms. Similar to Case Properties, 500 is definitely the number where the risk of issues exists. It’s important to test as you build.
In addition to what the system can handle, it’s also important to think about what the Healthcare Worker and Client can handle in terms of form length. Because you are using cases, take advantage of the option to have multiple follow up forms.
How to Test
Generally, we recommend testing your particular scenario with cases created using the Excel importer tool.